Looking at changing my diff fluids. I am finding some very conflicting info out there.

Some say 75/140 synthetic front and rear if you drive it hard

Others say 80/90 in the front and 75/140 in the rear

So if anyone actually knows...please enlighten me.

You did not say what year?
From an 08-11 Service Manual:
AXLES
CAPACITIES: U.S. / Metric

Front Axle
186 FIA (Model 30)
SAE 80W-90 Multipurpose Type,
GL-5 Gear Lubricant or equivalent.
2.6 Pints / 1.24 Liters

Rear Axle
8 1/4
SAE 75W-140 Synthetic Gear Lubricant or equivalent.
4.4 Pints / 2.08 Liters

From an earlier manual:
(basicly says the same thing)
Axle Differential (Front) Mopar Gear & Axle Lubricant (SAE 80W-90) or equivalent.
Axle Differential (Rear) Mopar Synthetic Gear Lubricant (SAE 75W-90) or equivalent.
For trailer towing, the lubricant should be replaced with Mopar Synthetic Gear & Axle Lubricant (SAE 75W-140) or equivalent.
Models equipped with Trac-Lok™ require a limited-slip additive.

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